U.S. patent application number 12/296370 was filed with the patent office on 2009-07-02 for novel ru complexes, production and use thereof.
This patent application is currently assigned to WACKER CHEMIE AG. Invention is credited to Hans-Juergen Eberle, Marco Hofmann, Johann Weis.
Application Number | 20090171056 12/296370 |
Document ID | / |
Family ID | 38121731 |
Filed Date | 2009-07-02 |
United States Patent
Application |
20090171056 |
Kind Code |
A1 |
Hofmann; Marco ; et
al. |
July 2, 2009 |
NOVEL RU COMPLEXES, PRODUCTION AND USE THEREOF
Abstract
Ruthenium compounds which have, in their ligand sphere, at least
one .eta..sup.6-bonded arene ligand and a silyl ligand; ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand to which is bonded a silyl or
siloxy radical directly or via a spacer, and ruthenium complexes
which have, in their ligand sphere, at least one .eta..sup.6-bonded
arene ligand and at least one further ligand to which is bonded a
silyl or siloxy radical directly or via a spacer are useful as
hydrosilylation catalysts.
Inventors: |
Hofmann; Marco; (Burghausen,
DE) ; Eberle; Hans-Juergen; (Munich, DE) ;
Weis; Johann; (Sauerlach, DE) |
Correspondence
Address: |
BROOKS KUSHMAN P.C.
1000 TOWN CENTER, TWENTY-SECOND FLOOR
SOUTHFIELD
MI
48075
US
|
Assignee: |
WACKER CHEMIE AG
Munich
DE
|
Family ID: |
38121731 |
Appl. No.: |
12/296370 |
Filed: |
March 28, 2007 |
PCT Filed: |
March 28, 2007 |
PCT NO: |
PCT/EP2007/052968 |
371 Date: |
October 7, 2008 |
Current U.S.
Class: |
528/15 ;
252/182.3; 556/479; 556/9 |
Current CPC
Class: |
C07F 17/02 20130101 |
Class at
Publication: |
528/15 ; 556/9;
556/479; 252/182.3 |
International
Class: |
C08G 77/00 20060101
C08G077/00; C07F 7/02 20060101 C07F007/02; C07F 7/08 20060101
C07F007/08; C09K 3/00 20060101 C09K003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 13, 2006 |
DE |
10 2006 017 594.8 |
Claims
1.-14. (canceled)
15. A silicophilic ligand-containing Ru compound of the formulae
(1a), (2a), (3(a-d)), 4, or 5 ##STR00015## where the two
SiR.sup.Si.sub.3 radicals are the same or different and each
R.sup.Si.sub.3 independently is a radical selected from the group
consisting of triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n--SiMe.sub.3, where n is from 1 to
500; and the R.sup.1 to R.sup.6 radicals are each independently
hydrogen, alkyl, aryl alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, wherein the alkyl, aryl and alkoxy radicals are
optionally substituted by SiRSi.sub.3 and OSiR.sup.Si.sub.3
radicals where R.sup.Si.sub.3 is optionally trialkyl; and two
adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure; ##STR00016## where the two SiR.sup.Si.sub.3 radicals are
as in formula (1a), the R.sup.1 and R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, with the proviso that the alkyl, aryl and alkoxy
radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where R.sup.Si.sub.3 is optionally
trihalogen, two adjacent R.sup.1 and R.sup.6 radicals optionally
form a ring structure, and L is an uncharged 2-electron donor
ligand; ##STR00017## where X is an anionic ligand; and L is an
uncharged 2-electron donor ligand; and L and X are optionally
joined to one another and, together with the ruthenium atom to
which they are bonded, and optionally form a ring which optionally
contains further atoms, the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, halogen,
SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, where the alkyl, aryl and
alkoxy radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, and with the further proviso that at
least one of the R.sup.1 to R.sup.6 radicals is an SiR.sup.Si.sub.3
radical, an OSiR.sup.Si.sub.3 radical or an alkyl, aryl or alkoxy
radical substituted by SiR.sup.Si.sub.3, OSiR.sup.Si.sub.3; and
R.sup.Si.sub.3 in the SiR.sup.Si.sub.3 and/or OSiR.sup.Si.sub.3
radicals are each independently trialkyl, triaryl, dialkylhalogen,
diarylhalogen, alkyl(aryl)halogen, alkyldihalogen, aryldihalogen,
trihalogen, dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
##STR00018## where the two SiR.sup.Si.sub.3 radicals are as defined
in formula (1a); the two SiRSi.sub.3 radicals are optionally joined
to one another via an R.sup.Si substituent; and the R.sup.1 to
R.sup.6 radicals are each independently hydrogen, alkyl, aryl,
alkoxy, SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, wherein the alkyl,
aryl and alkoxy radicals are optionally substituted by
SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals; and two adjacent
R.sup.1 to R.sup.6 radicals optionally form a ring structure;
##STR00019## where the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3, where the alkyl, aryl and alkoxy radicals are
optionally substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals; and where R.sup.Si.sub.3 is trialkyl, triaryl,
dialkylhalogen, diarylhalogen, alkyl(aryl)halogen, alkyldihalogen,
aryldihalogen, trihalogen, dialkyl(alkoxy), diaryl(alkoxy),
alkyl(aryl)alkoxy, alkyl(dialkoxy), aryl(dialkoxy), trialkoxy,
Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
and two adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure.
16. A compound of claim 15, wherein when R.sup.1 to R.sup.6 are
radicals substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals, R.sup.1 to R.sup.6 are selected from the group consisting
of --(CH.sub.2).sub.n--SiR.sup.Si.sub.3, --O--SiR.sup.Si.sub.3,
--O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer of 1
to 3.
17. A process for hydrosilylation in the presence of at least one
ruthenium hydrosilylation catalyst selected from the group
consisting of ruthenium complexes which have, in their ligand
sphere, at least one .eta..sup.6-bonded arene ligand and a silyl
ligand; ruthenium complexes which have, in their ligand sphere, at
least one .eta..sup.6-bonded arene ligand to which is bonded a
silyl or siloxy radical directly or via a spacer, and ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand and at least one further ligand to
which is bonded a silyl or siloxy radical directly or via a
spacer.
18. The process of claim 17, wherein at least one hydrosilylation
catalyst is a compound of the formulae (1a), (2a), (3(a-d)), 4, or
5 ##STR00020## where the two SiR.sup.Si.sub.3 radicals are the same
or different and each R.sup.Si.sub.3 independently is a radical
selected from the group consisting of triaryl, dialkylhalogen,
diarylhalogen, alkyl(aryl)halogen, alkyldihalogen, aryldihalogen,
trihalogen, dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
and the R.sup.1 to R.sup.6 radicals are each independently
hydrogen, alkyl, aryl alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, wherein the alkyl, aryl and alkoxy radicals are
optionally substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals where R.sup.Si.sub.3 is optionally trialkyl; and two
adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure; ##STR00021## where the two SiR.sup.Si.sub.3 radicals are
as in formula (Ia), the R.sup.1 and R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, with the proviso that the alkyl, aryl and alkoxy
radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where R.sup.Si.sub.3 is optionally
trihalogen, two adjacent R.sup.1 and R.sup.6 radicals optionally
form a ring structure, and L is an uncharged 2-electron donor
ligand; ##STR00022## where X is an anionic ligand; and L is an
uncharged 2-electron donor ligand; and L and X are optionally
joined to one another and, together with the ruthenium atom to
which they are bonded, and optionally form a ring which optionally
contains further atoms, the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, halogen,
SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, where the alkyl, aryl and
alkoxy radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, and with the further proviso that at
least one of the R.sup.1 to R.sup.6 radicals is an SiR.sup.Si.sub.3
radical, an OSiR.sup.Si.sub.3 radical or an alkyl, aryl or alkoxy
radical substituted by SiR.sup.Si.sub.3, OSiR.sup.Si.sub.3; and
R.sup.Si.sub.3 in the SiR.sup.Si.sub.3 and/or OSiR.sup.Si.sub.3
radicals are each independently trialkyl, triaryl, dialkylhalogen,
diarylhalogen, alkyl(aryl)halogen, alkyldihalogen, aryldihalogen,
trihalogen, dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
##STR00023## where the two SiR.sup.Si.sub.3 radicals are as defined
in formula (Ia); the two SiR.sup.Si.sub.3 radicals are optionally
joined to one another via an R.sup.Si substituent; and the R.sup.1
to R.sup.6 radicals are each independently hydrogen, alkyl, aryl,
alkoxy, SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, wherein the alkyl,
aryl and alkoxy radicals are optionally substituted by
SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals; and two adjacent
R.sup.1 to R.sup.6 radicals optionally form a ring structure;
##STR00024## where the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3, where the alkyl, aryl and alkoxy radicals are
optionally substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals; and where R.sup.Si.sub.3 is trialkyl, triaryl,
dialkylhalogen, diarylhalogen, alkyl(aryl)halogen, alkyldihalogen,
aryldihalogen, trihalogen, dialkyl(alkoxy), diaryl(alkoxy),
alkyl(aryl)alkoxy, alkyl(dialkoxy), aryl(dialkoxy), trialkoxy,
Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
and two adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure.
19. A hydrosilylatable composition comprising (A) a compound with
at least one aliphatically unsaturated carbon-carbon bond, (B) a
compound with at least one silicon-hydrogen bond and (D) a
ruthenium compound selected from the group consisting of ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand and a silyl ligand; ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand to which is bonded a silyl or
siloxy radical directly or via a spacer, and ruthenium complexes
which have, in their ligand sphere, at least one .eta..sup.6-bonded
arene ligand and at least one further ligand to which is bonded a
silyl or siloxy radical directly or via a spacer.
20. The hydrosilylatable composition of claim 19, wherein at least
one ruthenium compound of component (D) is a ruthenium compound of
the formulae (1a), (2a), (3(a-d)), 4, or 5 ##STR00025## where the
two SiR.sup.Si.sub.3 radicals are the same or different and each
R.sup.Si.sub.3 independently is a radical selected from the group
consisting of triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
and the R.sup.1 to R.sup.6 radicals are each independently
hydrogen, alkyl, aryl alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, wherein the alkyl, aryl and alkoxy radicals are
optionally substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals where R.sup.Si.sub.3 is optionally trialkyl; and two
adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure; ##STR00026## where the two SiR.sup.Si.sub.3 radicals are
as in formula (Ia), the R.sup.1 and R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 or
OSiR.sup.Si.sub.3, with the proviso that the alkyl, aryl and alkoxy
radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where R.sup.Si.sub.3 is optionally
trihalogen, two adjacent R.sup.1 and R.sup.6 radicals optionally
form a ring structure, and L is an uncharged 2-electron donor
ligand; ##STR00027## where X is an anionic ligand; and L is an
uncharged 2-electron donor ligand; and L and X are optionally
joined to one another and, together with the ruthenium atom to
which they are bonded, and optionally form a ring which optionally
contains further atoms, the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, halogen,
SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, where the alkyl, aryl and
alkoxy radicals are optionally substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, and with the further proviso that at
least one of the R.sup.1 to R.sup.6 radicals is an SiR.sup.Si.sub.3
radical, an OSiR.sup.Si.sub.3 radical or an alkyl, aryl or alkoxy
radical substituted by SiR.sup.Si.sub.3, OSiR.sup.Si.sub.3; and
R.sup.Si.sub.3 in the SiR.sup.Si.sub.3 and/or OSiR.sup.Si.sub.3
radicals are each independently trialkyl, triaryl, dialkylhalogen,
diarylhalogen, alkyl(aryl)halogen, alkyldihalogen, aryldihalogen,
trihalogen, dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
##STR00028## where the two SiR.sup.Si.sub.3 radicals are as defined
in formula (Ia); the two SiR.sup.Si.sub.3 radicals are optionally
joined to one another via an R.sup.Si substituent; and the R.sup.1
to R.sup.6 radicals are each independently hydrogen, alkyl, aryl,
alkoxy, SiR.sup.Si.sub.3 or OSiR.sup.Si.sub.3, wherein the alkyl,
aryl and alkoxy radicals are optionally substituted by
SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals; and two adjacent
R.sup.1 to R.sup.6 radicals optionally form a ring structure;
##STR00029## where the R.sup.1 to R.sup.6 radicals are each
independently hydrogen, alkyl, aryl, alkoxy, SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3, where the alkyl, aryl and alkoxy radicals are
optionally substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3
radicals; and where R.sup.Si.sub.3 is trialkyl, triaryl,
dialkylhalogen, diarylhalogen, alkyl(aryl)halogen, alkyldihalogen,
aryldihalogen, trihalogen, dialkyl(alkoxy), diaryl(alkoxy),
alkyl(aryl)alkoxy, alkyl(dialkoxy), aryl(dialkoxy), trialkoxy,
Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
or [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is from 1 to 500;
and two adjacent R.sup.1 to R.sup.6 radicals optionally form a ring
structure.
21. A silicone elastomer obtained by crosslinking a
hydrosilylatable composition of claim 19.
22. A coating obtained by crosslinking a hydrosilylatable
composition of claim 19.
Description
[0001] The invention relates to the preparation of Ru complexes
with silicophilic ligands and to the use thereof as catalysts in
transition metal-catalyzed hydrosilylation.
[0002] The addition of Si--H-functional compounds onto compounds
with aliphatic unsaturated bonds, especially C.dbd.C double bonds
(hydrosilylation), has already been known for some time.
[0003] Hydrosilylation allows Si-containing organic compounds,
organosilanes and organopolysiloxanes to be prepared. It is used
especially in the addition-crosslinking curing of
organopolysiloxanes in the silicone industry, for example for the
production of elastomers, molding materials in the dental industry
or antiadhesive coatings in the paper and films industry.
[0004] The catalysts used most frequently for the hydrosilylation
reaction are platinum and its compounds, the platinum being used in
metallic form, as metal fixed on an inorganic support, as a
platinum salt or in the form of a soluble or insoluble platinum
complex.
[0005] To date, for the majority of the hydrosilylation reactions
performed industrially, the so-called "Karstedt catalyst" known
from U.S. Pat. No. 3,715,334 and U.S. Pat. No. 3,775,452 is used,
which consists predominantly of a dimeric
platinum-tetramethyldivinylsiloxane complex, which can be described
by the formula [Pt.sub.2(TMDVS).sub.3]
(TMDVS=tetramethyldivinyldisiloxane). The Karstedt catalyst is
prepared proceeding from hexachloroplatinic acid H.sub.2PtCl.sub.6,
which is likewise frequently used as a hydrosilylation catalyst in
the form of an alcoholic solution.
[0006] Since platinum is one of the most expensive noble metals,
there have already been frequent efforts to use other metals and
compounds thereof as catalysts in hydrosilylation. For instance,
the prior art already discloses the use of the other platinum group
metals Pd, Rh, Ir, Ru in hydrosilylation. However, these have to
date been described as alternatives to Pt in particular as
catalysts for use in the case of specific substrates.
[0007] For example, US 2004/0092759 A1 and U.S. Pat. No. 5,559,264
describe Ru catalysts, for example RuCl.sub.3, RuBr.sub.3,
Ru(acac).sub.3, Ru/C, Ru.sub.3(CO).sub.12,
[RuCl.sub.2(CO).sub.3].sub.2, [Ru(COD)Cl.sub.2].sub.n
(COD=1,5-cyclo-octadiene), Ru(PPh.sub.3).sub.2(CO).sub.2Cl.sub.2
and Ru(PPh.sub.3).sub.3(CO)H.sub.2 for the hydrosilylation of
HSi(R).sub.x(OR).sub.3-x (x=0-2) with an olefinic halide, such as
allyl chloride.
[0008] EP 0403706 A2 describes the use of Ru complexes with at
least one tertiary phosphine ligand, for example
Ru(CO).sub.3(PPh.sub.3).sub.2, RuCl.sub.2(PPh.sub.3).sub.2, Ru(H)
(Cl) (PPh.sub.3).sub.3, Ru(PPh.sub.3).sub.4H.sub.2 and
Ru(CH.sub.2.dbd.CH.sub.2) (PPh.sub.3).sub.3 as catalysts for the
hydrosilylation of allylamines with SiH-functional silanes.
[0009] U.S. Pat. No. 5,248,802 describes the hydrosilylation of
trichlorosilane with olefinic nitriles, for example acrylonitrile,
in the presence of Ru-halogen or Ru-phosphine compounds, such as
RuCl.sub.3, RuBr.sub.3, RuI.sub.3, Ru(CO).sub.3(PPh.sub.3).sub.2,
RuCl.sub.2(PPh.sub.3).sub.3, Ru (H) (Cl) (PPh.sub.3).sub.3,
RuH.sub.2(PPh.sub.3).sub.4, Ru(CH.sub.2.dbd.CH.sub.2)
(PPh.sub.3).sub.3 and RuCl.sub.2(CO).sub.2(PPh.sub.3).sub.2.
[0010] Finally, DE 2810032 A1 describes the hydrosilylation of
dichlorosilane with olefins in the presence of Ru complexes, for
example RuCl.sub.2(PPh.sub.3).sub.3, Ru(H) (Cl) (PPh.sub.3).sub.3,
RuH.sub.3(PPh.sub.3).sub.3[Si(OMe).sub.3],
RuH.sub.3(PPh.sub.3).sub.3[Si(OMe).sub.2Ph] and RuH.sub.2
(PPh.sub.3).sub.4.
[0011] However, the use of other compounds with transition metals,
such as Ni, Co or Fe, as catalysts for hydro-silylations has also
already been described.
[0012] In general, these catalysts, however, are distinctly
inferior to the common Pt catalysts with regard to reactivity and
selectivity; especially for the crosslinking of polysiloxanes by
means of a hydrosilylation reaction, the rate and selectivity of
the non-Pt catalysts described to date for the hydrosilylation is
generally insufficient. From an economic point of view too, these
systems are usually not necessarily advantageous, since higher
catalyst concentrations have to be employed for the non-platinum
catalysts, and, in the case of rhodium, even higher costs than for
platinum are to be expected.
[0013] It was thus an object of the invention to provide an
alternative hydrosilylation catalyst. More particularly, it was an
object of the invention to provide a catalyst which is superior
both from an economic point of view and with regard to reactivity
and selectivity to the non-platinum hydrosilylation catalysts
described to date in the prior art and thus constitutes an
alternative to the Pt catalysts known from the prior art.
[0014] It has been found that, surprisingly, this object is
achieved by a particular class of Ru complexes which, in their
ligand sphere, have one or more silicophilic ligands and an
.eta..sup.6-bonded arene ligand. The .eta..sup.6-bonded arene
ligand may also itself be the silicophilic ligand.
[0015] Silicophilic ligands are understood hereinafter to mean
(a) silyl ligands bound or coordinated directly to the ruthenium
center; or (b) other ligands which are bound or coordinated to the
ruthenium center and in turn bear silyl and/or siloxy
substituents.
[0016] The silyl or siloxy substituents present on the ligand
coordinated to the ruthenium in the group (b) of silicophilic
ligands may be in the .alpha.-position to the coordination site of
the ligand or be bonded thereto via a spacer. The ligands are
preferably carbon n-bonded (olefinic, unsaturated) ligands. Among
the group (b) of silicophilic ligands, especially
.eta..sup.6-bonded arene ligands substituted by silyl or siloxy
substituents should be emphasized, where the silyl or siloxy
substituents may be bonded to the arene directly or via an
additional spacer. Such substituents simultaneously constitute the
inventive .eta..sup.6-bonded arene ligand and the silicophilic
ligand combined in one ligand in the ligand sphere of the
ruthenium.
[0017] Equally, in the case of presence of silicophilic ligands of
group (a), the .eta..sup.6-bonded arene ligand present in
accordance with the invention may optionally also simultaneously be
a ligand of group (b).
[0018] The invention provides a process for hydrosilylation
(hydrosilylation process) in the presence of a ruthenium catalyst,
characterized in that the ruthenium catalyst is selected from the
group comprising ruthenium complexes which have, in their ligand
sphere, at least one .eta..sup.6-bonded arene ligand and a silyl
ligand; ruthenium complexes which have, in their ligand sphere, at
least one .eta..sup.6-bonded arene ligand to which is bonded a
silyl or siloxy radical directly or via a spacer, and ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand and at least one further ligand to
which is bonded a silyl or siloxy radical directly or via a
spacer.
[0019] The invention further provides for the use of ruthenium
compounds selected from the group comprising ruthenium complexes
which have, in their ligand sphere, at least one .eta..sup.6-bonded
arene ligand and a silyl ligand; ruthenium complexes which have, in
their ligand sphere, at least one .eta..sup.6-bonded arene ligand
to which is bonded a silyl or siloxy radical directly or via a
spacer, and ruthenium complexes which have, in their ligand sphere,
at least one .eta..sup.6-bonded arene ligand and at least one
further ligand to which is bonded a silyl or siloxy radical
directly or via a spacer as hydrosilylation catalysts.
[0020] The ruthenium center in these complexes may in principle be
present in all oxidation states common for organometallic ruthenium
complexes, especially in the 0, +II, +III, +IV oxidation states.
Preference is given to complexes with the 0, +II and +IV oxidation
states of ruthenium.
[0021] The use of the inventive compounds as catalysts in
hydrosilylation is notable especially for the fact that the
catalysts are very active, selective and universally usable
catalysts which are nevertheless free of platinum.
[0022] The silicophilic ligands of the catalyst make the compound
silicone-like, thus leading to the effect that the catalyst is
generally completely miscible into silanes, siloxanes or
polysiloxanes to be hydrosilylated and hence result in completely
homogeneous reaction mixtures. This leads to a high activity of the
compounds. Associated with this high activity is generally
additionally also a high hydrosilylation selectivity in the sense
of a comparatively low level of side reactions, such as
hydrogenation or dehydrogenating silylation with simultaneously
moderate catalyst concentrations needed.
[0023] One possible embodiment of Ru complexes for the inventive
use with silyl ligands bonded or coordinated directly to the
ruthenium center is that of compounds of the general formula
(1)
##STR00001##
where the two SiR.sup.Si.sub.3 radicals may be the same or
different and R.sup.Si.sub.3 overall is a radical selected from the
group comprising trialkyl, triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2. (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is
from 1 to 500; and the R.sup.1 to R.sup.6 radicals are each
independently selected from the group comprising hydrogen (H),
alkyl, aryl and alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3,
with the proviso that the alkyl, aryl and alkoxy radicals may
optionally in turn be substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where R.sup.Si.sub.3 here is as defined
above; and two adjacent R.sup.1 to R.sup.6 radicals may optionally
form a further ring, for example a naphthyl radical.
[0024] When R.sup.1 to R.sup.6 in the compounds of the general
formula (1) are radicals substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, they are preferably selected from the
group comprising --(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--O--SiR.sup.Si.sub.3, --O(CH.sub.2).sub.n--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer from
1 to 3 and R.sup.Si.sub.3 is as defined above.
[0025] Compounds of the general formula (1) in which R.sup.Si.sub.3
overall is a trialkyl radical are already known from the prior art
as (.eta..sup.6-arene)Ru(H).sub.2(SiR.sub.3).sub.2 where
.eta..sup.6-arene=C.sub.6H.sub.6, C.sub.6Me.sub.6,
p-Me--C.sub.6H.sub.4-iPr, and R.sub.3=Me.sub.3, or where
.eta..sup.6-arene=C.sub.6H.sub.6 and R.sub.3=Et.sub.3, from Berry
et al., Organometallics 1994, 13, 2551-2553.
[0026] The invention further provides compounds of the general
formula (1a)
##STR00002##
where the two SiR.sup.Si.sub.3 radicals may be the same or
different and R.sup.Si.sub.3 overall is a radical selected from the
group comprising triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is
from 1 to 500; and the R.sup.1 to R.sup.6 radicals are each
independently selected from the group comprising hydrogen (H),
alkyl, aryl and alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3,
with the proviso that the alkyl, aryl and alkoxy radicals may
optionally in turn be substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where R.sup.Si.sub.3 here is selected
from the group specified above and additionally trialkyl; and two
adjacent R.sup.1 to R.sup.6 radicals may optionally form a further
ring, for example a naphthyl radical.
[0027] When R.sup.1 to R.sup.6 in the compounds of the general
formula (Ia) are radicals substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, they are preferably selected from the
group comprising --(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--O--SiR.sup.Si.sub.3, --O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer from
1 to 3 and R.sup.Si.sub.3 is defined as specified for the general
formula (1a).
[0028] Preferred radicals for SiR.sup.Si.sub.3 are selected from
the group comprising Me(OSiMe.sub.3).sub.2,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy]-SiMe.sub.3, where n is in each case from 1
to 500. The R.sup.1 to R.sup.6 radicals are preferably selected
from hydrogen (H) and alkyl.
[0029] Specific, particularly preferred embodiments for the
inventive use and for the inventive compounds are the following
compounds of the formulae (1b), (1c) and (1d).
##STR00003##
where n in each case is from 1 to 500.
[0030] An alternative possible embodiment of Ru complexes for the
inventive use with silyl ligands bonded or coordinated directly to
the ruthenium center is that of compounds of the general formula
(2)
##STR00004##
where the two SiR.sup.Si.sub.3 radicals may be the same or
different and R.sup.Si.sub.3 overall is a radical selected from the
group comprising trialkyl, triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is
from 1 to 500; and
[0031] the R.sup.1 to R.sup.6 radicals are each independently
selected from the group comprising hydrogen (H), alkyl, aryl and
alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3, with the proviso
that the alkyl, aryl and alkoxy radicals may optionally in turn be
substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals
where R.sup.Si.sub.3 is as defined above; and
two adjacent R.sup.1 to R.sup.6 radicals may optionally form a
further ring, for example a naphthyl radical; and L is an uncharged
2-electron donor ligand.
[0032] Preferred embodiments of the uncharged 2-electron donor
ligands L are CO and phosphines, especially trialkyl- or
triarylphosphines.
[0033] When R.sup.1 to R.sup.6 in the compounds of the general
formula (2) are radicals substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, they are preferably selected from the
group comprising --(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--O--SiR.sup.Si.sub.3, --O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer from
1 to 3 and R.sup.Si.sub.3 is as defined above.
[0034] Compounds of the general formula (2) in which R.sup.Si.sub.3
overall is a trihalogen radical and L=CO are already known from the
prior art as (.eta..sup.6-arene)Ru(CO) (SiCl.sub.3).sub.2 where
.eta..sup.6-arene=C.sub.6H.sub.5Me, C.sub.6H.sub.4Me.sub.2,
C.sub.6H.sub.3Me.sub.3, C.sub.6H.sub.2Me.sub.4, C.sub.6Me.sub.6,
C.sub.6H.sub.5tBu, p-C.sub.6H.sub.4-tBu.sub.2, C.sub.6H.sub.5Cl
from Pomeroy et al., J. Organomet. Chem. 1979, 177, C27-C28;
Chemical Communications 1980, 661-663.
[0035] The invention further provides compounds of the general
formula (2a)
##STR00005##
where the two SiR.sup.Si.sub.3 radicals may be the same or
different and R.sup.Si.sub.3 overall is a radical selected from the
group comprising trialkyl, triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, dialkyl(alkoxy),
diaryl(alkoxy), alkyl(aryl)alkoxy, alkyl(dialkoxy), aryl(dialkoxy),
trialkoxy, Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2,
(OSiMe.sub.3).sub.3, (dialkylsiloxy).sub.n-SiMe.sub.3,
(diarylsiloxy).sub.n-SiMe.sub.3 and
[alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is from
1 to 500; and the R.sup.1 to R.sup.6 radicals are each
independently selected from the group comprising hydrogen (H),
alkyl, aryl and alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3,
with the proviso that the alkyl, aryl and alkoxy radicals may
optionally in turn be substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals where RSi3 here is selected from the
group specified above and additionally trihalogen; and two adjacent
R.sup.1 to R.sup.6 radicals may optionally form a further ring, for
example a naphthyl radical; and
[0036] L is an uncharged 2-electron donor ligand.
[0037] Preferred embodiments of a 2-electron donor ligand L are CO
and phosphines, especially trialkyl- or triaryl-phosphines.
[0038] When R.sup.1 to R.sup.6 in the compounds of the general
formula (2a) are radicals substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, they are preferably selected from the
group comprising --(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--O--SiR.sup.Si.sub.3, --O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer from
1 to 3 and R.sup.Si.sub.3 is defined as specified for the compounds
of the general formula (2a).
[0039] Preferred radicals for SiR.sup.Si.sub.3 are selected from
the group comprising Me(OSiMe.sub.3).sub.2,
(dialkylsiloxy).sub.n-(SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n is in each case
from 1 to 500. The R.sup.1 to R.sup.6 radicals are preferably
selected from hydrogen (H) and alkyl. Preferably, L is selected
from the group comprising CO, PPh.sub.3 and PMe.sub.3.
[0040] Specific, particularly preferred embodiments for the
inventive use and for the inventive compounds are the following
compounds of the formulae (2b), (2c) and (2d).
##STR00006##
where n in each case is from 1 to 500.
[0041] In the case that no silyl ligands bonded or coordinated
directly to the ruthenium center are present, the inventive silyl
and/or siloxy substituents may in principle be bonded to any
ligands for ruthenium as substituents which are known to the
skilled person from the prior art. Particular preference is given
to the presence of the silyl and/or siloxy substituents directly on
the inventive .eta..sup.6-bonded arene ligands. Possible
embodiments of such Ru complexes are compounds of the general
formulae (3a), (3b), (3c) and (3d)
##STR00007##
where X is an anionic ligand, especially selected from the group
comprising hydride (H), halide, alkoxy, siloxy, acetate and
trifluoroacetate; and L is an uncharged 2-electron donor ligand,
preferably selected from the group comprising N-functional ligands,
especially nitriles and pyridines; P-functional ligands, especially
tertiary phosphines, for example trialkyl- and triarylphosphines,
ditertiary phosphines, for example bis(diphenylphosphino)methane
(dppm) and bis(diphenylphosphino)ethane (dppe); tertiary arsines;
tertiary stibines; oxygen ligands, for example acetone; sulfur
ligands, for example DMSO, and carbon ligands, for example CO and
isonitriles; and L and X are optionally joined to one another and,
together with the ruthenium atom to which they are bonded, may form
a ring which may contain further atoms, the R.sup.1 to R.sup.6
radicals are each independently selected from the group comprising
hydrogen (H), alkyl, aryl, alkoxy, halogen, SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3, where the alkyl, aryl and alkoxy radicals may
optionally in turn be substituted by SiR.sup.Si.sub.3 and
OSiR.sup.Si.sub.3 radicals, and combined with the proviso that at
least one of the R.sup.1 to R.sup.6 radicals is an SiR.sup.Si.sub.3
radical, an OSiR.sup.Si.sub.3 radical or an alkyl, aryl or alkoxy
radical substituted by SiR.sup.Si.sub.3, OSiR.sup.Si.sub.3; and
SiR.sup.Si.sub.3 and/or OSiR.sup.Si.sub.3 radicals present may be
the same or different, where R.sup.Si.sub.3 overall is a radical
selected from the group comprising trialkyl, triaryl,
dialkylhalogen, diarylhalogen, alkyl(aryl)halogen, alkyldihalogen,
aryldihalogen, trihalogen, dialkyl(alkoxy), diaryl(alkoxy),
alkyl(aryl)alkoxy, alkyl(dialkoxy), aryl(dialkoxy), trialkoxy,
Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is
from 1 to 500.
[0042] When R.sup.1 to R.sup.6 in the compounds of the general
formula (3a), (3b), (3c) and (3d) are radicals substituted by
SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals, they are
preferably selected from the group comprising
--(CH.sub.2).sub.m--SiR.sup.Si.sub.3, --O--SiR.sup.Si.sub.3,
--O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer of 1
to 3 and R.sup.Si.sub.3 is as defined above.
[0043] Preferably, in the compounds of the general formula (3a),
(3b), (3c) and (3d), one R.sup.1 to R.sup.6 radical (in the case of
compounds of the general formula (3a), in each case one R.sup.1 to
R.sup.6 radical per arene ligand) is an SiR.sup.Si.sub.3,
OSiR.sup.Si.sub.3 or an alkyl, aryl and alkoxy radical substituted
by SiR.sup.Si.sub.3 OSiR.sup.Si.sub.37 especially of the preferred
embodiment specified.
[0044] In the case of cationic complexes, such as those of the
general formula (3c) and (3d), in addition to halide, it is
possible to use noncoordinating or weakly coordinating anions,
especially selected from the group comprising BF.sub.4.sup.-,
PF.sub.6.sup.-, BPh.sub.4.sup.-.
[0045] One possible embodiment in which L and X are joined to one
another and, together with the ruthenium atom to which they are
bonded, form a ring would be an acetylacetonato ligand.
[0046] One possible particularly preferred embodiment of a compound
of the general formula (3a) is a compound of the formula (3e)
##STR00008##
where x is from 0 to 3; and n is from 1 to 500.
[0047] A further preferred embodiment of inventive Ru complexes in
which no silyl ligands bonded or coordinated directly to the
ruthenium center are present is that of .eta..sup.2-bonded olefinic
ligands with silyl substituents of the general formula (4)
##STR00009##
where the two SiR.sup.Si.sub.3 radicals may be the same or
different, where R.sup.Si.sub.3 overall is a radical selected from
the group comprising trialkyl, triaryl, dialkylhalogen,
diarylhalogen, alkyl(aryl)halogen, alkyldihalogen, aryldihalogen,
trihalogen, dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy)-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3 and
[alkyl(aryl)siloxy]1-SiMe.sub.3, where n in each case is from 1 to
500; and the two SiR.sup.Si.sub.3 radicals may optionally be joined
to one another via an R.sup.51 substituent in each case; and
[0048] the R.sup.1 to R.sup.6 radicals are each independently
selected from the group comprising hydrogen (H), alkyl, aryl and
alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3, with the proviso
that the alkyl, aryl and alkoxy radicals may optionally in turn be
substituted by SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals,
where R.sup.Si.sub.3 is as defined above; and
two adjacent R.sup.1 to R.sup.6 radicals may optionally form a
further ring, for example a naphthyl radical.
[0049] Possible preferred embodiments are compounds of the general
formulae (4a), (4b) and (4c)
##STR00010##
where n is from 1 to 500.
[0050] A particularly preferred embodiment in which the two
SiR.sup.Si.sub.3 radicals are optionally joined to one another via
in each case one R.sup.Si substituent via an oxygen atom and thus
form a bidentate divinylsiloxane ligand is that of compounds of the
general formula (5)
##STR00011##
where the R.sup.1 to R.sup.6 radicals are each independently
selected from the group comprising hydrogen (H), alkyl, aryl,
alkoxy, SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3, where the alkyl,
aryl and alkoxy radicals may optionally in turn be substituted by
SiR.sup.Si.sub.3 and OSiR.sup.Si.sub.3 radicals; and where
R.sup.Si.sub.3 overall is a radical selected from the group
comprising trialkyl, triaryl, dialkylhalogen, diarylhalogen,
alkyl(aryl)halogen, alkyldihalogen, aryldihalogen, trihalogen,
dialkyl(alkoxy), diaryl(alkoxy), alkyl(aryl)alkoxy,
alkyl(dialkoxy), aryl(dialkoxy), trialkoxy, Me(OSiMe.sub.3).sub.2,
Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3, where n in each case is
from 1 to 500; and two adjacent R.sup.1 to R.sup.6 radicals may
optionally form a further ring, for example a naphthyl radical.
[0051] When R.sup.1 to R.sup.6 in the compounds of the general
formulae (4) and (5) are radicals substituted by SiR.sup.Si.sub.3
and OSiR.sup.Si.sub.3 radicals, they are preferably selected from
the group comprising --(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--O--SiR.sup.Si.sub.3, --O(CH.sub.2).sub.m--SiR.sup.Si.sub.3,
--(CH.sub.2).sub.m--OSiR.sup.Si.sub.3 and
--O(CH.sub.2).sub.m--OSiR.sup.Si.sub.3, where m is an integer of 1
to 3 and R.sup.Si.sub.3 is in each case as defined above.
[0052] Possible preferred embodiments are compounds of the formulae
(5a), (5b) and (5c).
##STR00012##
[0053] The statements which follow apply equally to all embodiments
specified herein, especially to the compounds of the general
formulae (1), (1a), (1b), (1c), (1d), (2), (2a), (2b), (2c), (2d),
(3a), (3b), (3c), (3d), (3e), (4), (4a), (4b), (4c), (5), (5a),
(5b) and (5c).
[0054] Particular preference is given to uncharged complexes for
the inventive use and for use in the process according to the
invention.
[0055] Particular preference is given to complexes in which
R.sup.Si.sub.3 is a radical selected from the group comprising
Me(OSiMe.sub.3).sub.2, Ph(OSiMe.sub.3).sub.2, (OSiMe.sub.3).sub.3,
(dialkylsiloxy).sub.n-SiMe.sub.3, (diarylsiloxy).sub.n-SiMe.sub.3
and [alkyl(aryl)siloxy].sub.n-SiMe.sub.3 radical, where n in each
case is from 1 to 500, since these complexes have a high similarity
to siloxanes. The particular advantage of such R.sup.u compounds is
their good solubility in polysiloxanes, as are used in the
crosslinking reaction of silicones.
[0056] n is generally from 1 to 500. n is preferably from 1 to 250,
more preferably from 10 to 200.
[0057] Preference is given to selecting the R.sup.1 to R.sup.6
radicals from the group comprising hydrogen (H), alkyl radicals and
alkyl radicals substituted by SiR.sup.Si.sub.3 radicals, where
R.sup.Si.sub.3 is in turn selected from the above-mentioned
preferred radicals.
[0058] The inventive Ru complexes can be synthesized by standard
methods known in principle to the person skilled in the art from
the prior art.
[0059] Inventive compounds which have, directly in their ligand
sphere, a silyl ligand (direct Ru--Si bond), especially those
compounds of the general formulae (1) and (2), can be obtained
either via
(a) oxidative addition of SiH-functional silanes and siloxanes onto
suitable arene-Ru precursors (for example according to J. Y. Corey,
J. Braddock-Wilking, Chem. Rev. 1999, 99, 175-292); or (b)
oxidative addition of SiH-functional silanes and siloxanes onto
suitable Ru precursors and subsequent ligand/arene exchange, as
described in Science of Synthesis, 2001, Georg Thieme Verlag,
Stuttgart, New York, volume 1, p. 931-936.
[0060] The inventive compounds which have, in their ligand sphere,
ligands which in turn bear silyl and/or siloxy substituents,
especially those compounds of the general formulae (3) to (5), can
be obtained by reaction of common ruthenium precursors--optionally
with simultaneous reduction of the Ru precursor with a suitable
reducing agent, especially zinc, magnesium and ethanol (with
Na.sub.2CO.sub.3--with appropriate ligands into which appropriate
substituents have been introduced by means of standard
organosilicon chemistry methods, especially by means of metathesis
reactions using Grignard reagents, lithium organyls,
hydrosilylations or Birch reductions. Ruthenium-vinylsilane or
-siloxane compounds of the general formula (4) and (5) can also be
prepared via ligand exchange processes with the appropriate
vinylsilanes and -siloxanes, optionally with reduction of the Ru
precursor with a suitable reducing agent, especially zinc,
magnesium and ethanol (with Na.sub.2CO.sub.3).
[0061] The inventive catalysts, especially those of the general
formulae (1) to (5), are used generally in such an amount as to
result in an Ru content of 10-1000 ppm, preferably 50-500 ppm,
based on the total mass of the reacting substrates.
[0062] The hydrosilylation reactions using the inventive catalysts
are effected generally at temperatures between room temperature,
especially 20.degree. C., and 200.degree. C., preferably between
50.degree. C. and 160.degree. C., and a pressure of 900 to 1100
hPa. However, it is also possible to employ higher or lower
temperatures and pressures.
[0063] The hydrosilylation reactions can be performed either under
air or under an inert gas atmosphere (nitrogen, argon), preference
being given to reaction under inert gas atmosphere.
[0064] The process according to the invention and the inventive use
of the ruthenium catalysts can generally be effected in all
hydrosilylation reactions which are known to the person skilled in
the art from the prior art and are described, for example, in
Walter Noll "Chemie und Technologie der Silicone" [Chemistry and
Technology of the Silicones], Verlag Chemie GmbH, Weinheim/Bergstr.
1968; Bogdan Marciniec, "Comprehensive Handbook on
Hydrosilylation", Oxford: Pergamon Press, 1992, and they are
generally used in all hydrosilylatable, especially crosslinkable,
compositions known from the prior art.
[0065] The inventive use of the catalysts and the process according
to the invention are suitable both for the synthesis of low
molecular weight compounds and for the curing of higher molecular
weight compounds, especially of polymers with unsaturated groups,
especially with carbon-carbon double bonds.
[0066] In particular, those hydrosilylation reactions in which
C.dbd.C-functional polysiloxanes are reacted with SiH-functional
polysiloxanes or C.dbd.C-functional organo-silanes are reacted with
SiH-functional organosilanes are catalyzed.
[0067] Preference is given in particular to the reaction of
vinyl-terminal polydimethylsiloxanes with SiH-functional
polysiloxanes of the general formula
Me.sub.3SiO--[Si(H)(Me)O].sub.x--SiMe.sub.3, where x is from 1 to
500, especially from 1 to 100, and of Si-vinyl-functional
organosilanes with Si--H-functional organosilanes.
[0068] Specific examples of Si-vinyl-functional organosilanes which
can be hydrosilylated by the process according to the invention or
with the inventive use of the catalysts include
vinyltrimethylsilane, vinyltriethoxy-silane,
vinylmethyldiethoxysilane, vinylmethyldimeth-oxysilane,
vinyltrichlorosilane.
[0069] Specific examples of SiH-functional organosilanes include
HSi(OR').sub.3 where R' is an alkyl radical,
HSi(Me).sub.3-xCl.sub.x where x is from 1 to 3, and HSiR''.sub.3
where R'' is an alkyl or aryl radical.
[0070] The invention further relates to hydrosilylatable
compositions comprising
(A) a compound with at least one aliphatically unsaturated
carbon-carbon bond, (B) a compound with at least one
silicon-hydrogen bond and (D) a ruthenium compound, characterized
in that the ruthenium compound is selected from the group
comprising ruthenium complexes which have, in their ligand sphere,
at least one .eta..sup.6-bonded arene ligand and a silyl ligand;
ruthenium complexes which have, in their ligand sphere, at least
one .eta..sup.6-bonded arene ligand to which is bonded a silyl or
siloxy radical directly or via a spacer, and ruthenium complexes
which have, in their ligand sphere, at least one .eta..sup.6-bonded
arene ligand and at least one further ligand to which is bonded a
silyl or siloxy radical directly or via a spacer.
[0071] A preferred embodiment of the hydrosilylatable compositions
concerns polyorganosiloxane compositions comprising
(A) polyorganosiloxanes which have radicals with aliphatic
carbon-carbon multiple bonds, (B) polyorganosiloxanes with
Si-bonded hydrogen atoms or instead of (A) and (B) (C)
polyorganosiloxanes which comprise SiC-bonded radicals with
aliphatic carbon-carbon multiple bonds and Si-bonded hydrogen
atoms, and (D) a ruthenium compound, characterized in that the
ruthenium compound is selected from the group comprising ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand and a silyl ligand; ruthenium
complexes which have, in their ligand sphere, at least one
.eta..sup.6-bonded arene ligand to which is bonded a silyl or
siloxy radical directly or via a spacer, and ruthenium complexes
which have, in their ligand sphere, at least one .eta..sup.6-bonded
arene ligand and at least one further ligand to which is bonded a
silyl or siloxy radical directly or via a spacer.
[0072] The ruthenium compound of component (D) functions in each
case as a hydrosilylation catalyst (ruthenium catalyst). Preference
is given to using compounds of the general formula (1) to (5),
especially one or more of the above-specified embodiments.
[0073] Hydrosilylatable compositions are especially crosslinkable
compositions.
[0074] Components (A), (B) and (C) described for the
hydrosilylatable compositions correspond to the compounds
(reactants) to be converted in the process according to the
invention. Both the inventive compositions and the processes
according to the invention and the use are based on the same
inventive ruthenium catalysts.
[0075] The process according to the invention for hydrosilylation
is carried out by supplying energy, especially by supplying heat.
The same applies to the inventive hydrosilylatable
compositions.
[0076] The inventive hydrosilylatable compositions preferably
comprise compounds which have at least one aliphatically
unsaturated carbon-carbon bond and are selected from the group
comprising vinyl-functional organosilanes and vinyl-terminal
polydimethylsiloxanes, and compounds having at least one
silicon-hydrogen bond which are selected from the group comprising
SiH-functional polysiloxanes and Si--H-functional
organosilanes.
[0077] The invention likewise relates to silicone elastomers
obtainable by crosslinking the above-described inventive
hydrosilylatable compositions, especially the polyorganosiloxane
compositions described.
[0078] The invention likewise relates to coatings, especially
antiadhesive coatings, for example for producing release, backing
and interleaving papers obtainable by crosslinking the
above-described inventive hydrosilylatable compositions, especially
the polyorganosiloxane compositions described.
[0079] The invention likewise relates to polysiloxane or
organosilane compositions which are produced by the process
according to the invention and are usable, for example, for
producing dental imprints, adhesives, release liners, flat gaskets,
sealants and coatings.
[0080] As is well known, the compounds (A) and (B) or (C) used in
the inventive compositions are selected such that crosslinking is
possible. For example, compound (A) has at least two aliphatically
unsaturated radicals and siloxane (B) at least three Si-bonded
hydrogen atoms, or compound (A) has at least three aliphatically
unsaturated radicals and siloxane (B) at least two Si-bonded
hydrogen atoms, or else, instead of compound (A) and (B), siloxane
(C) is used, which has aliphatically unsaturated radicals and
Si-bonded hydrogen atoms in the abovementioned ratios.
[0081] The compound (A) used in accordance with the invention may
also be silicon-free organic compounds with preferably at least two
aliphatically unsaturated groups, and also organosilicon compounds
having preferably at least two aliphatically unsaturated groups.
Examples of organic compounds which can be used as component (A) in
the inventive compositions are 1,3,5-trivinylcyclohexane,
2,3-dimethyl-1,3-butadiene, 7-methyl-3-methylene-1,6-octadiene,
2-methyl-1,3-butadiene, 1,5-hexadiene, 1,7-octadiene,
4,7-methylene-4,7,8,9-tetrahydroindene, methylcyclopentadiene,
5-vinyl-2-norbornene, bicyclo[2.2.1]-hepta-2,5-diene,
1,3-diisopropenylbenzene, vinyl-containing polybutadiene,
1,4-divinylcyclohexane, 1,3,5-triallylbenzene,
1,3,5-trivinylbenzene, 1,2,4-trivinylcyclohexane,
1,3,5-triisopropenylbenzene, 1,4-divinylbenzene,
3-methyl-1,5-heptadiene, 3-phenyl-1,5-hexadiene,
3-vinyl-1,5-hexadiene, and 4,5-dimethyl-4,5-diethyl-1,7-octadiene,
N,N'-methylenebis(acrylamide), 1,1,1-tris(hydroxymethyl)propane
triacrylate, 1,1,1-tris(hydroxymethyl)propane trimethacrylate,
tripropylene glycol diacrylate, diallyl ether, diallylamine,
diallyl carbonate, N,N'-diallylurea, triallylamine,
tris(2-methylallyl)amine, 2,4,6-triallyloxy-1,3,5-triazine,
triallyl-s-triazine-2,4,6(1H,3H,5H)-trione, diallyl malonate,
polyethylene glycol diacrylate, polyethylene glycol dimethacrylate,
poly(propylene glycol) methacrylate.
[0082] However, the inventive silicone compositions preferably
comprise, as constituent (A), an aliphatically unsaturated
organosilicon compound, for which all aliphatically unsaturated
organosilicon compounds used to date in addition-crosslinking
compositions may be used, and also, for example, silicone block
copolymers with urea segments, silicone block copolymers with amide
segments and/or imide segments and/or ester amide segments and/or
polystyrene segments and/or silarylene segments and/or carborane
segments and silicone graft copolymers with ether groups.
[0083] The organosilicon compounds (A) used, which have SiC-bonded
radicals with aliphatic carbon-carbon multiple bonds, are
preferably linear or branched organopolysiloxanes composed of units
of the average general formula (X)
R.sub.aR.sup.y.sub.bSiO.sub.(4-a-b)/2 formula (X)
where [0084] R may be the same or different and is an organic
radical free of aliphatic carbon-carbon multiple bonds, [0085]
R.sup.y may be the same or different and is a monovalent,
optionally substituted, SiC-bonded hydrocarbon radical with an
aliphatic carbon-carbon multiple bond, [0086] a is 0, 1, 2 or 3 and
[0087] b is 0, 1 or 2, with the proviso that the sum of a+b is less
than or equal to 3, and an average of at least 2 R.sup.y radicals
are present per molecule.
[0088] The R radicals in the general formula (X) may be mono- or
polyvalent radicals, in which case the polyvalent radicals, such as
bivalent, trivalent and tetravalent radicals, may join a plurality
of, for instance two, three or four, siloxy units of the general
formula (X) to one another.
[0089] R includes especially the monovalent radicals --F, --Cl,
--Br, --OR.sup.x, --CN, --SCN, --NCO and SiC-bonded, optionally
substituted hydrocarbon radicals which may be interrupted by oxygen
atoms or the --C(O)-- group, and also bivalent radicals Si-bonded
on both sides of the general formula (X). R.sup.x is generally
hydrogen or a monovalent, optionally substituted hydrocarbon
radical having from 1 to 20 carbon atoms, preferably hydrogen,
alkyl radicals and aryl radicals.
[0090] Examples of R.sup.x radicals are alkyl radicals such as the
methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, isobutyl,
tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl radical,
hexyl radicals such as the n-hexyl radical, heptyl radicals such as
the n-heptyl radical, octyl radicals such as the n-octyl radical
and isooctyl radicals such as the 2,2,4-trimethylpentyl radical,
nonyl radicals such as the n-nonyl radical, decyl radicals such as
the n-decyl radical, cycloalkyl radicals such as the cyclopropyl,
cyclopentyl, cyclohexyl, cycloheptyl radicals and methylcyclohexyl
radicals, unsaturated radicals such as the allyl, 5-hexenyl,
7-octenyl, cyclohexenyl and styryl radical, aryl radicals such as
phenyl radicals, o-, m- or p-tolyl radicals, xylyl radicals and
ethylphenyl radicals, aralkyl radicals such as the benzyl radical
and the .alpha.- and .beta.-phenylethyl radical.
[0091] Examples of halogenated R.sup.x radicals are haloalkyl
radicals such as the 3,3,3-trifluoro-n-propyl radical, the
2,2,2,2',2',2'-hexafluoroisopropyl radical, the
heptafluoroisopropyl radical, and haloaryl radicals such as the o-,
m- or p-chlorophenyl radical.
[0092] R.sup.x is preferably hydrogen, alkyl radicals and aryl
radicals, particular preference being given to hydrogen, the methyl
radical and the ethyl radical.
[0093] If the R radicals are SiC-bonded, substituted hydrocarbon
radicals, preferred substituents are halogen atoms,
phosphorus-containing radicals, cyano radicals, --OR.sup.x,
--NR.sup.x--, --NR.sup.x.sub.2, --NR.sup.x--,
--C(O)--NR.sup.x.sub.2, --C(O)--NR.sup.x.sub.2, --C(O)--R.sup.x,
--C(O)OR.sup.x, --SO.sub.2-Ph and --C.sub.6F.sub.5 where R.sup.x is
as defined above and Ph is a phenyl radical.
[0094] Examples of R radicals are alkyl radicals such as the
methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl,
n-pentyl, isopentyl, neopentyl, tert-pentyl radical, hexyl radicals
such as the n-hexyl radical, heptyl radicals such as the n-heptyl
radical, octyl radicals such as the n-octyl radical and isooctyl
radicals such as the 2,2,4-trimethylpentyl radical, nonyl radicals
such as the n-nonyl radical, decyl radicals such as the n-decyl
radical, dodecyl radicals such as the n-dodecyl radical, and
octadecyl radicals such as the n-octadecyl radical, cycloalkyl
radicals such as the cyclopentyl, cyclohexyl, cycloheptyl and
methylcyclohexyl radicals, aryl radicals such as the phenyl,
naphthyl, anthryl and phenanthryl radicals, alkaryl radicals such
as o-, m-, p-tolyl radicals, xylyl radicals and ethylphenyl
radicals, and aralkyl radicals such as the benzyl radical, the
.alpha.- and the .beta.-phenylethyl radical.
[0095] Examples of substituted R radicals are haloalkyl radicals
such as the 3,3,3-trifluoro-n-propyl radical, the
2,2,2,2',2',2'-hexafluoroisopropyl radical, the
heptafluoroisopropyl radical, haloaryl radicals such as the o-, m-
and p-chlorophenyl radical, --(CH.sub.2).sub.n--N(R.sup.x)
C(O)NR.sup.x.sub.2, --(CH.sub.2).sub.n--C(O)NR.sup.x.sub.2,
--(CH.sub.2).sub.n--C(O) R.sup.x, --(CH.sub.2).sub.n--C(O)OR.sup.x,
--(CH.sub.2).sub.n--C(O)NR.sup.x.sub.2, --(CH.sub.2).sub.n--C(O)--
(CH.sub.2).sub.m--C(O)CH.sub.3,
--(CH.sub.2).sub.n--NR.sup.x--(CH.sub.2).sub.m--NR.sup.x.sub.2,
--(CH.sub.2).sub.n--O--CO--R.sup.x, --(CH.sub.2).sub.n--O--
(CH.sub.2).sub.m--CH(OH)--CH.sub.2OH,
--(CH.sub.2).sub.n--(OCH.sub.2CH.sub.2).sub.m--OR.sup.x,
--(CH.sub.2)--SO.sub.2-Ph and
--(CH.sub.2).sub.n--O--C.sub.6F.sub.5, where R.sup.x is as defined
above, n and m are identical or different integers from 0 to 10 and
Ph denotes the phenyl radical.
[0096] Examples of R as bivalent radicals Si-bonded on both sides
of the general formula (X) are those which derive from the above
monovalent examples mentioned for the R radical by substitution of
a hydrogen atom for an additional bond. Examples of such radicals
are --(CH.sub.2).sub.n--, --CH(CH.sub.3)--, --C(CH.sub.3).sub.2--,
--CH(CH.sub.3)--CH.sub.2--, --C.sub.6H.sub.4--,
--CH(Ph)--CH.sub.2--, --C(CF.sub.3).sub.2--,
--(CH.sub.2).sub.n--C.sub.6H.sub.4--(CH.sub.2).sub.n--,
--(CH.sub.2).sub.n--C.sub.6H.sub.4--C.sub.6H.sub.4--(CH.sub.2).sub.n--,
--(CH.sub.2O).sub.m--, --(CH.sub.2CH.sub.2O).sub.m--,
--(CH.sub.2).sub.n--O.sub.x--C.sub.6H.sub.4--SO.sub.2--C.sub.6H.sub.4--O.-
sub.x--(CH.sub.2).sub.n--, where x is 0 or 1, m and n are each as
defined above and Ph is the phenyl radical.
[0097] The R radical is preferably a monovalent, SiC-bonded,
optionally substituted hydrocarbon radical which has from 1 to 18
carbon atoms and is free of aliphatic carbon-carbon multiple bonds,
more preferably a monovalent SiC-bonded hydrocarbon radical which
has from 1 to 6 carbon atoms and is free of aliphatic carbon-carbon
multiple bonds, especially the methyl or phenyl radical.
[0098] The R.sup.y radicals may be any groups amenable to an
addition reaction (hydrosilylation) with an SiH-functional
compound.
[0099] If the R.sup.y radicals are SiC-bonded, substituted
hydrocarbon radicals, preferred substituents are halogen atoms,
cyano radicals and --OR.sup.x where R.sup.x is as defined
above.
[0100] The R.sup.y radicals are preferably alkenyl and alkynyl
groups having from 2 to 16 carbon atoms, such as vinyl, allyl,
methallyl, 1-propenyl, 5-hexenyl, ethynyl, butadienyl, hexadienyl,
cyclopentenyl, cyclopentadienyl, cyclohexenyl,
vinylcyclohexylethyl, divinylcyclohexylethyl, norbornenyl,
vinylphenyl and styryl radicals, particular preference being given
to using vinyl, allyl and hexenyl radicals.
[0101] The molecular weight of constituent (A) may vary within wide
limits, for instance between 10.sup.2 and 10.sup.6 g/mol. For
example, constituent (A) may be a relatively low molecular weight
alkenyl-functional oligosiloxane such as
1,3-divinyltetramethyldisiloxane, but may also be a highly
polymerized polydimethylsiloxane having pendant or terminal
Si-bonded vinyl groups, for example having a molecular weight of
10.sup.5 g/mol (number-average determined by means of NMR). Nor is
the structure of the molecules forming constituent (A) fixed; in
particular, the structure of a relatively high molecular weight,
i.e. oligomeric or polymeric, siloxane may be linear, cyclic,
branched or else resinous, network-like. Linear and cyclic
polysiloxanes are preferably composed of units of the formula
R.sub.3SiO.sub.1/2, R.sup.yR.sub.2SiO.sub.1/2, R.sup.yRSiO.sub.2/2
and R.sub.2SiO.sub.2/2, where R and R.sup.y are each as defined
above. Branched and network-like polysiloxanes additionally contain
trifunctional and/or tetrafunctional units, preference being given
to those of the formulae RSiO.sub.3/2, R.sup.ySiO.sub.3/2 and
SiO.sub.4/2. It will be appreciated that it is also possible to use
mixtures of different siloxanes which satisfy the criteria of
constituent (A).
[0102] As component (A), particular preference is given to the use
of vinyl-functional, substantially linear polydiorganosiloxanes
having a viscosity of from 0.01 to 500 000 Pas, more preferably
from 0.1 to 100 000 Pas, in each case at 25.degree. C.
[0103] The organosilicon compounds (B) used may be all
hydrogen-functional organosilicon compounds which have also been
used to date in addition-crosslinkable compositions.
[0104] The organopolysiloxanes (B) used, which have Si-bonded
hydrogen atoms, are preferably linear, cyclic or branched
organopolysiloxanes composed of units of the average general
formula (X.sub.1)
R.sub.cH.sub.dSiO.sub.(4-c-d)/2 formula (XI)
in which [0105] R may be the same or different and is as defined
above, [0106] c is 0, 1, 2 or 3 and [0107] d is 0, 1 or 2, with the
proviso that the sum of c+d is less than or equal to 3 and, on
average, at least two Si-bonded hydrogen atoms are present per
molecule.
[0108] The organopolysiloxane (B) used in accordance with the
invention preferably contains Si-bonded hydrogen in the range from
0.04 to 1.7 percent by weight based on the total weight of the
organopolysiloxane (B).
[0109] The molecular weight of constituent (B) may likewise vary
within wide limits, for instance between 10.sup.2 and 10.sup.6
g/mol. For example, constituent (B) may be a relatively low
molecular weight SiH-functional oligosiloxane, such as
tetramethyldisiloxane, but also a highly polymerized
polydimethylsiloxane having pendant or terminal SiH groups, or a
silicone resin having SiH groups. Nor is the structure of the
molecules which form constituent (B) fixed; in particular, the
structure of a relatively high molecular weight, i.e. oligomeric or
polymeric, SiH-containing siloxane may be linear, cyclic, branched
or else resinous, network-like. Linear and cyclic polysiloxanes are
preferably composed of units of the formula R.sub.3SiO.sub.1/2,
HR.sub.2SiO.sub.1/2, HRSiO.sub.2/2 and R.sub.2SiO.sub.2/2, where R
is as defined above. Branched and network-like polysiloxanes
additionally contain trifunctional and/or tetrafunctional units,
preference being given to those of the formulae RSiO.sub.3/2,
HSiO.sub.3/2 and SiO.sub.4/2. It will be appreciated that it is
also possible to use mixtures of different siloxanes which satisfy
the criteria of constituent (B). In particular, the molecules which
form constituent (B), in addition to the obligatory SiH groups, may
optionally at the same time also contain aliphatically unsaturated
groups. Particular preference is given to the use of low molecular
weight SiH-functional compounds such as
tetrakis(dimethylsiloxy)silane and tetramethylcyclotetrasiloxane,
and also higher molecular weight, SiH-containing siloxanes such as
poly(hydromethyl)siloxane and poly(dimethylhydromethyl)siloxane
with a viscosity at 25.degree. C. of from 10 to 10 000 mPas, or
analogous SiH-containing compounds in which some of the methyl
groups have been replaced by 3,3,3-trifluoropropyl or phenyl
groups.
[0110] Constituent (B) is present in the inventive crosslinkable
overall silicone compositions preferably in such an amount that the
molar ratio of SiH groups to aliphatically unsaturated groups is
from 0.1 to 20, more preferably between 1.0 and 5.0.
[0111] The components (A) and (B) used in accordance with the
invention are commercial products or preparable by processes common
in chemistry.
[0112] Instead of component (A) and (B), the inventive compositions
may comprise organopolysiloxanes (C) which have aliphatic
carbon-carbon multiple bonds and Si-bonded hydrogen atoms.
[0113] If siloxanes (C) are used, they are preferably those
composed of units of the formulae
[0114] R.sub.gSiO.sub.4-g/2, R.sub.hR.sup.ySiO.sub.3-h/2 and
R.sub.iHSiO.sub.3-i/2,
where R and R.sup.y are each as defined above, g is 0, 1, 2 or 3, h
is 0, 1 or 2 and i is 0, 1 or 2, with the proviso that at least 2
R.sup.y radicals and at least 2 Si-bonded hydrogen atoms are
present per molecule.
[0115] Examples of organopolysiloxanes (C) are those composed of
SiO.sub.4/2, R.sub.3SiO.sub.1/2, R.sub.2R.sup.ySiO.sub.1/2 and
R.sub.2HSiO.sub.1/2 units, so-called MQ resins which may
additionally contain RSiO.sub.3/2 and R.sub.2SiO units, and also
linear organopolysiloxanes substantially consisting of
R.sub.2R.sup.ySiO.sub.1/2, R.sub.2SiO and RHSiO units where R and
R.sup.y are each as defined above.
[0116] The organopolysiloxanes (C) preferably have an average
viscosity of from 0.01 to 500 000 Pas, more preferably from 0.1 to
100 000 Pas, in each case at 25.degree. C.
[0117] Organopolysiloxanes (C) are preparable by methods common in
chemistry.
[0118] Apart from components (A) to (D), the inventive curable
compositions may also comprise all further substances which have
also been used to date to produce addition-crosslinkable
materials.
[0119] Examples of reinforcing fillers which may be used as
component (E) in the inventive materials are fumed or precipitated
silicas having BET surface areas of at least 50 m.sup.2/g, and also
carbon blacks and activated carbons such as furnace black and
acetylene black, preference being given to fumed and precipitated
silicas having BET surface areas of at least 50 m.sup.2/g.
[0120] These silica fillers may have hydrophilic character or be
hydrophobized by known processes. When hydrophilic fillers are
incorporated, the addition of a hydrophobizing agent is
required.
[0121] The content in the inventive crosslinkable material of
actively reinforcing filler (E) is in the range from 0 to 70% by
weight, preferably from 0 to 50% by weight.
[0122] The inventive compositions, especially the
polyorgano-siloxane materials, may optionally comprise, as
constituent (F), further additives in a proportion of up to 70% by
weight, preferably from 0.0001 to 40% by weight. These additives
may, for example, be inactive fillers, resinous polyorganosiloxanes
other than siloxanes (A), (B) and (C), dispersing assistants,
solvents, adhesion promoters, pigments, dyes, plasticizers, organic
polymers, heat stabilizers, etc. They include additives such as
quartz flour, diatomaceous earth, clays, chalk, lithopone, carbon
blacks, graphite, metal oxides, metal carbonates and sulfates,
metal salts of carboxylic acids, metal dusts, fibers such as glass
fibers, polymer fibers, polymer powders, dyes, pigments, etc. The
inventive compositions, especially the organopolysiloxane
materials, can be prepared by known processes, for example by
homogeneously mixing the individual components. The sequence is as
desired, but preference is given to the homogeneous mixing of the
inventive ruthenium catalyst (D) with a mixture of (A) and (B) or
(C), and optionally (E) and (F). The ruthenium catalyst (D) used in
accordance with the invention can be incorporated as a solid
substance or as a so-called batch--mixed homogeneously with a small
amount of (A) or (A) with (E). The mixing is effected, depending on
the viscosity of (A), for example, with a stirrer, in a dissolver,
on a roller or in a kneader.
[0123] The examples which follow serve to illustrate the inventive
use, the process according to the invention and the inventive
compositions, and should in no way at all be considered as a
restriction.
EXAMPLES
Preparation of the Catalysts
Example 1
Synthesis of
(p-cymene)Ru(H).sub.2[(SiMe.sub.2O).sub.xSiMe.sub.3].sub.2
(x.apprxeq.14)
##STR00013##
[0125] A mixture of 50 mg (0.08 mmol) of
[(p-cymene)RuCl.sub.2].sub.2 in 10 ml of tetrahydrofuran is admixed
with 740 mg (approx. 0.67 mmol) of
HMe.sub.2Si--[O--SiMe.sub.2].sub.x--OSiMe.sub.3 and the mixture is
heated to 80.degree. C. for 15 h. After cooling, all volatile
constituents are removed under reduced pressure. The residue is
taken up in 20 ml of n-pentane and filtered through Florisil, and
the filtrate is concentrated by evaporation under reduced pressure.
There remains a brown oil. Yield 243 mg (62%).
[0126] .sup.1H NMR (300 MHz, C.sub.6D.sub.6): d=5.52 (s, br, 4H,
C.sub.6H.sub.4), 2.44 [sept, 1H, CH(CH.sub.3).sub.2], 2.01 (s, 3H,
CH.sub.3), 1.11 [d, 6H, (CH.sub.3).sub.2CH], 0.70 [s, 12H,
(CH.sub.3).sub.2Si--Ru], 0.24-0.17 [(CH.sub.3).sub.2Si--O,
SiMe.sub.3], -13.18 ppm (s, 2H, H--Ru)
Example 2
Synthesis of (p-cymene)Ru(h.sup.4-TMDVS)
##STR00014##
[0128] A mixture of 995 mg (1.63 mmol) of
[(p-cymene)RuCl.sub.2].sub.2, 958 mg (9.03 mmol) of
Na.sub.2CO.sub.3 (anhydrous) and 5.75 g (30.8 mmol) of
divinyltetramethyldisiloxane in 50 ml of ethanol is heated under
reflux at 90.degree. C. for 4 h. After cooling, all volatile
constituents are removed under reduced pressure. The residue is
admixed with 50 ml of n-heptane, extracted at 40.degree. C. for 1 h
and filtered while warm through Celite in a preheated filter. The
filtrate is concentrated to a volume of 5 ml and subjected to
column chromatography using Al.sub.2O.sub.3 (neutral, activity
level I, eluent: n-pentane). The evaporative concentration of the
eluted yellow zone affords a yellow-orange oil. Yield: 346 mg
(25%).
[0129] .sup.1H NMR (300 MHz, C.sub.6D.sub.6): d=4.39 (s, br, 4H,
C.sub.6H.sub.4), 3.84-2.64 (m, 6H, H.sub.2C.dbd.CH--Si), 2.30
[sept, 1H, CH(CH.sub.3).sub.2], 1.79 (s, 3H, CH.sub.3), 1.07 [d,
6H, (CH.sub.3).sub.2CH], 0.46 (s, 6H, CH.sub.3Si), 0.38 ppm (s, 6H,
CH.sub.3Si)
Study of the Catalytic Properties
Example 3
Hydrosilylation of HMe.sub.2SiO--[SiMe.sub.2O].sub.x--SiMe.sub.2H
(x.apprxeq.13) (H-polymer 13) with 3-vinylheptamethyltri-siloxane
and the catalyst
(p-cymene)Ru(H).sub.2[(SiMe.sub.2O).sub.x--SiMe.sub.3].sub.2 (from
Example 1) at 160.degree. C.
[0130] A mixture of 2.5 g (approx. 2.63 mmol) of H-polymer 13 and
1.44 g (5.78 mmol) of 3-vinylheptamethyltrisiloxane is admixed with
28.4 mg of
(p-cymene)Ru(H).sub.2[(SiMe.sub.2O).sub.x--SiMe.sub.3].sub.2
(approx. 300 ppm of Ru) (obtainable by a process according to
Example 1) and stirred at 160.degree. C. The hydrosilylation
reaction (conversion, selectivity, yield) is analyzed by .sup.1H
NMR.
TABLE-US-00001 Reaction Conversion Selectivity Yield time [%] [%]
[%] 15 min. 89 91 81 1 h 97 89 87
Comparative Example 1
Ru-Arene Catalyst without Si-Substituted Ligand; Hydrosilylation of
HMe.sub.2SiO--[SiMe.sub.2O].sub.x--SiMe.sub.2H (x.apprxeq.13)
(H-polymer 13) with 3-vinyl-heptamethyltrisiloxane and the catalyst
[(p-cymene)-RuCl.sub.2].sub.2 at 160.degree. C.
[0131] A mixture of 2.51 g (approx. 2.63 mmol) of H-polymer 13 and
1.44 g (5.78 mmol) of 3-vinylheptamethyltrisiloxane is admixed with
4.6 mg of [(p-cymene)RuCl.sub.2].sub.2 (384 ppm of Ru), and stirred
at 160.degree. C. The hydrosilylation reaction (conversion,
selectivity, yield) is analyzed by .sup.1H NMR.
TABLE-US-00002 Reaction Conversion Selectivity Yield time [%] [%]
[%] 15 min. 84 63 53 1 h 93 66 61
Comparative Example 2
Pt catalyst; Hydrosilylation of
HMe.sub.2SiO--[SiMe.sub.2O].sub.x--SiMe.sub.2H (x.apprxeq.13)
(H-polymer 13) with 3-vinylheptamethyltrisiloxane and the Karstedt
Catalyst Pt.sub.2(TVDMS).sub.3 at 120.degree. C.
[0132] A mixture of 2.51 g (approx. 2.63 mmol) of H-polymer 13 and
1.44 g (5.78 mmol) of 3-vinylheptamethyltrisiloxane is admixed with
19 .mu.l of a solution (2% Pt) of the Karstedt catalyst in xylene
(96 ppm of Pt), and stirred at 120.degree. C. The hydrosilylation
reaction (conversion, selectivity, yield) is analyzed by .sup.1H
NMR.
TABLE-US-00003 Reaction Conversion Selectivity Yield time [%] [%]
[%] 15 min. 100 91 91
Example 4
Hydrosilylation of HMe.sub.2SiO--[SiMe.sub.2O].sub.x--SiMe.sub.2H
(x.apprxeq.13) (H-polymer 13) with 3-vinylheptamethyl-trisiloxane
and the catalyst (p-cymene)Ru(h.sup.4-TMDVS) (from Example 2) at
120.degree. C.
[0133] A mixture of 2.5 g (approx. 2.63 mmol) of H-polymer 13 and
1.44 g (5.78 mmol) of 3-vinylheptamethyltrisiloxane is admixed with
5.1 mg of (p-cymene)Ru(h.sup.4-TMDVS) (approx. 300 ppm of Ru)
(obtainable by a process according to Example 2) and stirred at
120.degree. C. The hydrosilylation reaction (conversion,
selectivity, yield) is analyzed by .sup.1H NMR.
TABLE-US-00004 Reaction Conversion Selectivity Yield time [%] [%]
[%] 15 min. 67 73 49 1 h 94 72 68
Example 5
Crosslinking of an .alpha.,.omega.-divinylpolydimethyl-siloxane
with an SiH-functional polysiloxane at 120.degree. C.
[0134] 10 g of an .alpha.,.omega.-divinylpolydimethylsiloxane,
viscosity .eta.=500 mPas (name within Wacker VIPO 500) are admixed
with the Ru catalyst (300 ppm of Ru based on the total mass of the
mixture), mixed vigorously in a round-bottom flask and admixed with
250 mg of an SiH-functional polysiloxane of the formula
Me.sub.3SiO--[Si(H)Me--O].sub.48--SiMe.sub.3 (name within Wacker
V24 crosslinker) and mixed vigorously once again.
[0135] The mixture is stirred in a preheated oil bath at
120.degree. C. and 500 rpm. The time until the gelation has
progressed to such an extent that stirring with a magnetic stirrer
bar is no longer completely possible is determined.
TABLE-US-00005 Gelation time Catalyst
(p-cymene)Ru(H).sub.2(SiEt.sub.3).sub.2 11 min. 20 s
(p-cymene)Ru(H).sub.2[(SiMe.sub.2O).sub.x--SiMe.sub.3].sub.2 8 min.
20 s (p-cymene)Ru(h.sup.4-TMDVS) 4 min. 10 s Comparative Example
[(p-cymeme)RuCl.sub.2].sub.2 38 min. [Pt.sub.2(TMDVS).sub.3],
"Karstedt catalyst" <5 s (100 ppm Pt)
Example 6
Crosslinking of an .alpha.,.omega.-divinylpolydimethyl-siloxane
with an SiH-functional polysiloxane in thin layers at 120.degree.
C.
[0136] The mixture from Example 3 is applied to a microscope slide
as a layer with a doctor blade (60.mu.) and heated on a heating
bench at 120.degree. C.
[0137] The quality of the crosslinking is determined by a rub-off
test, which is carried out after certain times, with a rating
according to the following criteria: [0138] 6: fluid system [0139]
5: fluid system with partially crosslinked zones [0140] 4:
crosslinked layer, destroyed after 1 finger rub [0141] 3:
crosslinked layer, destroyed after 2-4 finger rubs [0142] 2:
crosslinked layer, destroyed after >4 finger rubs [0143] 1:
crosslinked layer which cannot be destroyed by finger rubs
TABLE-US-00006 [0143] Microscope slide Catalyst
(p-cymene)Ru(H).sub.2[(SiMe.sub.2O).sub.x--SiMe.sub.3].sub.2 1
min.: 5 5 min.: 4 10 min.: 3 20 min.: 2
(p-cymene)Ru(H).sub.2(SiEt.sub.3).sub.2 1 min.: 6 5 min.: 5 10
min.: 4 20 min.: 3 Comparative Examples
[(p-cymene)RuCl.sub.2].sub.2 1 min.: 6 5 min.: 5 10 min.: 5 20
min.: 5 Ru(CO).sub.3(PPh.sub.3).sub.2 1-20 min.: 6.sup.
* * * * *